Available S-Function Implementations
You can implement your S-function in one of five ways:
A handwritten C MEX S-function provides
the most programming flexibility. You can implement your algorithm
as a C MEX S-function or write a wrapper S-function to call existing
C, C++, or Fortran code. Writing a new S-function requires knowledge
of the S-function API and, if you want to generate inlined code for
the S-function, the Target Language Compiler (TLC).
The S-Function Builder is
a graphical user interface for programming a subset of S-function
functionality. If you are new to writing C MEX S-functions, you can
use the S-Function Builder to generate new S-functions or incorporate
existing C or C++ code without interacting with the S-function API.
The S-Function Builder can also generate TLC files for inlining your
S-function during code generation with the Real-Time Workshop product.
The Legacy Code Tool is
a set of MATLAB commands that helps you create an S-function
to incorporate legacy C or C++ code. Like the S-Function Builder,
the Legacy Code Tool can generate a TLC file to inline your S-function
during code generation. The Legacy Code Tool provides access to fewer
of the methods in the S-function API than the S-Function Builder or
a handwritten C MEX S-function.
The following sections describe the uses, features, and differences
of these S-function implementations. The last section compares using
a handwritten C MEX S-function, the S-Function Builder, and the Legacy
Code Tool to incorporate an existing C function into your Simulink model.
 | Selecting an S-Function Implementation | | What Type of S-Function Should You Use? |  |
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